Piercing-mill guide



UNITED STATES PATENT OFFICE.

HARRY McQUAID, OF CANTON, OHIO, ASSIGNOB TO THE TIMKEN ROLLER BEARING COMPANY, OF CANTON, OHIO, A CORPORATION OF OHIO.

PIERCING-MILL GUIDE.

No Drawing.

To all whom it may concern Be it known that I HARRY MoQUAIn, a citizen of the United States, and a resident of the city of Canton, in the county of Stark and State of Ohio, have invented a new and useful Improvement in Piercing-Mill Guides, of which the following is a specification.

My invention relates to the guides used in the manufacture of metal tubesfor guiding the hot stock to the piercing mill to be pierced thereby and has for its principal object to avoid great losses incidental to the Wearing away of guides unequally. It consists prmcipally in manufacturing the guides out of direct furnace iron as hereinafter de scribed.

Guides of piercing mills are exposed to' great heat by the contact of the hot stock or tubes thereon; and at the same time they are exposed to considerable abrasion not only from the tube or stock but'from the scale or foreignmatter trapped between the guide and the stock. As a consequence, such guides Wear away rapidly and usually wearaway unequally so that hard spots are left projecting above the surface of the worn soft spots. Under such conditions, the tube is frequently scored so badly as to compel the discarding thereof, and the guide itself must either be redressed or scraped.

The great losses incidental to the use of such guides are well known and have led to" numerous attempts to find a suitable metal that will stand the hard conditions to which it is exposed and at the same time Wear evenly. As a result of experiment and observation, I have found that direct furnace iron is suitable for this purpose. By the Specification of Letters Patent.

Patented Dec. 21, 1920.

Application filed October 27, 1919. Serial No. 838,623.

term direct furnace iron, I mean cast-iron that is cast directly into the molds for the guides without being allowed to cool after leaving the blast furnace. Guides thus formed are of a metal of even and homogeneous texture and strength, that endures the heat and, what is of greater importance, that wears evenly and smoothly. Such guides wear much more evenly than guides now in common use, and therefore are more durable, as they give much greater service before they have to be discarded because of rou h sur ace which scores the tubes.

hile my invention is not limited to the exact composition of direct furnace iron, I have found that metal of the following composition gives very satisfactory results, namely, total carbon 3 per cent. (of which 2.50 per cent. is combined), manganese .40 per cent., phosphorus .072 per cent., sulfur 08 per cent., silicon .60 per cent., balance iron.

What I claim is:

1. A piercing mill guide made of direct furnace iron.

2. A guide for piercing mills of the kind described and the like consisting of cast-iron cast without cooling after leaving the blast furnace.

3. A guide for piercing mills and the like consisting of direct furnace iron of substantially the following composition, .namely: total carbon 3 per cent. (of which 2.50 per cent. is combined), manganese .40 per cent., phosphorus .072 per cent., sulfur .08 per cent., silicon .60 per cent., balance iron.

Signed at Canton, Ohio, this 22nd day of 

